Currently, there is what should be considered a bug in the room editor. The bounds of the asset scroll area background are fixed around the size of the room, instead of the bounding box of instances and tiles within the room. This makes it difficult, if not impossible, to edit instances and tiles outside of the room.
GameMaker added this starting with version 8.1, but LGM always had it. What's interesting is that GM8.1 removed scrollbars from the room editor completely by offering middle mouse pan, while LGM still managed to keep them. I don't have a preference either way if we keep the scrollbars, but I do think we need to compute a bounding box around the instances and tiles of the room to fix the scrollbars to allow you to go outside the room, or else add middle mouse pan like GM8.1. It would also be ok to do both.
Currently, there is what should be considered a bug in the room editor. The bounds of the asset scroll area background are fixed around the size of the room, instead of the bounding box of instances and tiles within the room. This makes it difficult, if not impossible, to edit instances and tiles outside of the room.
GameMaker added this starting with version 8.1, but LGM always had it. What's interesting is that GM8.1 removed scrollbars from the room editor completely by offering middle mouse pan, while LGM still managed to keep them. I don't have a preference either way if we keep the scrollbars, but I do think we need to compute a bounding box around the instances and tiles of the room to fix the scrollbars to allow you to go outside the room, or else add middle mouse pan like GM8.1. It would also be ok to do both.